The techniques and management methods practised at the 'Inverliever rainbow trout farm', a pilot scheme situated south of Oban, in Scotland, are described. Subterranean water is pumped (rate of flow approx 35 m super(3)/min) into lake Awe which has a surface area of approx 60 km super(2). The pumped water is channelled along 126 raceways (42 series of 3) each measuring 30 m in length and 1.80 m in breadth. After use the water is emptied back into the lake via a 50 m pipe which opens at a depth of 15 m at the bottom of the lake. The distribution of food pellets is ensured every 3 hr for adult fish and more frequently for younger fish. The stock of eggs obtained from reproducing females in the basins is supplemented by imported eggs from Denmark and USA in winter and Australia and Tasmania in summer. The eggs are incubated and the young reared until they weigh 4-5 g. Fish weighing 180-240 g are selected, the guts removed, suitably packed and immediately frozen.